Acoustical correction machine



March 11, 1941. s, wu m 2,234,789

ACOUSTICAL commoner: MACHINE Filed D80. 15, 1938 2 SheeEs-Sheet 1 llfitl il I-Ii! IN V EN TDR. r MILTON 5. NUNDER'LIC H BY 8 g a 3% 3' ATTORNEY March 11, 1941- I M. s. WUNDERLICH 2,2 ,789

ACOUSTICAL CORRECTION MACHINE Filed Dec. 15, 1938 2 Sheets-Sheet 2 IIIIIA ITIIIA. III

1/ Q INVENTOR.

M/LTON 5. WUNUERL/CH aienied Mar. ll, 1941 ACOUSTICAL CORRECTION MACHINE Milton s. Wunderlich, International Falls, Minn., assignor to The Insulite Company, Minneapolis, Minn, a corporation of Minnesota Application December 15, 1938, Serial No. 245,873

2 Claims.

This invention pertains to betterments and improvements in the acoustical correction of rooms. halls, auditoriums, and the like, and involves the use of means for forming perforations 5 or apertures extending into the wall surface, particularly of walls having sound absorbing material covering the surfaces thereof whereby the sound waves passing into the surface are absorbed or dissipated. One object of the invention is to provide an apparatus which will form perforations or apertures in the ceilings and thereby provide a sound absorbing construction of high eficiency and one which at the time will aflord a surface which may be decorated in the usual way without interfering with the sound deadening properties.

Another aim of the invention is to afford a procedure by which walls and the like may have openings formed into or through the surface in situ, prior to decoration or after decoration of the wall surface.

The present invention has a superiority over the prior art of giving the sound absorbing wall surfaced rooms the required acoustical correction needed in the particular enclosure.

Other and further objects of the invention will appear in the course of the following description and the invention resides in the novel features and the combination of parts which will be particularly used in the claims.

This invention is capable of numerous forms and variations without departing from the essential features herein disclosed. It is, therefore, the intent and desire that the embodiment shown herein be deemed illustrative and not restricted, and that the patent shall cover all features of patentable novelty existing in the invention disclosed, reference being had to the claims rather than to the specific description herein to indicate the scope of the invention.

in the drawings forming part of this application similar characters of reference indicate corresponding parts in all the views.

Fig. l is a view in elevation of the new improved acoustical drilling machine.

Fig. 2 is a top plan view of the drill head.

Fig. 3 is the side elevational view of the drill head.

Fig. 4. is a view taken on lines lt of Fig. 1. till Fig. 5 is a sectional view taken on line 5-5 of Figure 1.

Fig. 6 is a modified form of the acoustical drilling machine. V

Fig. 'i is a side elevational view of the drill head shown in Fig. 6.

til

hill

RIM-110) Fig. 8 is a view taken along lines 8-8 of Fig. 6.

Fig. 9 is a sectional view with part of the drill head broken away.

Referring to the drawings in detail the acoustical perforating machine includes a base iii which may be and preferably is supported by ball bearing rollers ii. Secured to the base Ill is frame H, which is so constructed that a source of power such as an electrical motor I may be located within frame 12. The motor M is secured to a dish-shaped member 15 which is fastened to the base it. Secured to the upper end of frame i2 is a hollow casing member i3. Movably supported in member I3 is a tubular casing I6 which is provided near one end thereof with rack teeth ll. Pinion i8 is adapted to engage rack teeth ii for the purpose of permitting raising and lowering of the drill head, hereinafter to be most specifically described. Handle 19 is adapted to be secured to the pinion l8 and this handle should be of sufficient length that the raising and lowering of the drill head may be accomplished with comparative ease. Telescopically secured in member i6 is an upper tubular casing 20. Casing 20 can be secured in the adjusted positions by suitable means such as a bolt and nut 2|. Drill head 22 is supported by easing 2i! and carried by the upper plate 23 of the drill head 22, are guide members 24. Operatively encircling portions of members 24 are elastic tension members such as springs 25. The extent to which members 24 can be compressed are controlled by threaded adjusting bolts 26. Secured to casing it at the upper end of member I3 is shoulder member ll. To the drive shaft of the motor M is operatively connected drive shaft 28 the upper end of which is hollow to receive the square solid end of the upper drive shaft 29. Suitably loctated within the supporting casings iii and 2d are bearings such as 3%.

Operation.--Speciflcally, by way of example, the acoustical correction of any room may be accomplished in the following manner: for example, ceiling 32 or any enclosure has applied thereto sound absorbing material 33 such as vegetable fiber board. When it has been determined the amount of acoustical correction required for the enclosure and the location in the room. where such correction is required the drilling apparatus is adjusted to the desired or required height so that the drilling of the ceiling may be easily accomplished. The operator after locating the drilling head in the proper position applies force downwardly on handle it which results in the forcing upwardly and in contact with the material to beperforated, drills of head 22. When handle it is forced downwardly, the casings i6 and Biigare forced upwardly, thus carrying the head 22 toward the ceiling. The depth to which the material is perforated is controlled by mem bers 26, springs 25 and bolts 26.

In Fig. 6 is shown a modified form of the acoustical drilling machine. This form is particularly adapted for drilling in corners, around lights and various other structures in which the form shown in Fig. 1 could not readily be used. The form shown in Fig. 6 consists of base i6 supported by suitable rollers H. Supported by base 46 is telescoping casings and 36 and the height to which the stand are to be used can be adjusted and secured in the adjusted position by member 3?. Support member 35 is secured rigidly in member 38 which is preferably formed integral with member 40 and these together with member 39 form a hinge member which is adapted to pivot on shaft 4!. This shaft 4! extends through hinge member 42 which enables the upper portion of the drill stand to be moved without the necessity of moving the base "I. Shaft 44 is secured to the base It) and likewise secured to the hinge member 42. The upper end of supporting member 36 is provided with tubular member 45 which is suitably secured to frame 46 at 44a. The spaced apart members 46 are secured together by members 41 and secured to members 41 and 46 are supporting rods 48 and 49. Secured to the upper end of 49 is drill head support 50 for supporting the drill head 22. The drill head may be identical with that used and shown with apparatus disclosed in Fig. 1.

For guiding and properly locating the drill head 22, a rod 5| is secured to member 49 and is provided with handle 52 at the lower end thereof. Member 48 has secured at the upper end thereof supporting platform 53 which is adapted to rest and be secured to power transmitting device 54 which may be an electrical motor. This motor 54 is adapted to drive the drill through the medium of drive belt 55 and drive pulley 56. Drive pulley 56 is operatively secured to stub shaft 51 and the upper end of stub shaft 51 is secured to gear 58 which is adapted to enmesh in operative condition with gears 60 which in turn drive gears 6i and 62 and thereby the drills 65 are caused'to revolve. In the form of acoustical drilling machine shown in Fig. 6 it is essential that the operator be able to force the drill head against the material to be perforated and this may be accomplished by securing to the frame 46, a rod .chain or other means 61. The rod 61 is secured to the frame 36 at 66. A handle member 66 is pivotally secured to the casing 35 at 66, and rod. in is secured to the handle member 69 at 16.

The operation of this form of the drilling machine is very similar to that of the form shown in Fig. 1, therefore, a description of the operation of the machine is deemed to be unnecessary.

The number of drills to be carried by head 22 may be varied and depends in part upon the area that it is desired to treat.

While fiber board has been shown as the sound absorbing material it is to be understood that various plasters may be used and the plaster perforated if desired. In the case of fiber board plaster base the perforations may extend through the plaster and into the base.

It will be obvious to those familiar with sound insulating materials that effectiveness of my new system of acoustical treatment is in the penetra tion of the sound waves into the opening formed where the energy is dissipated in the sound absorbing material.

The drills or perforating means are preferably so arranged that they revolve in the opposite direction to screw direction of the drill. The direction of rotation of the perforating means forces into the wall substantially all of the material removed from the wall surface and does not permit it to escape into the room.

What I claim is:

1. A drilling apparatus for perforating sound absorbing material in situ including a drill head having a cover plate, a plurality of drills operatively mounted in the drill head and passing through the cover plate, adjustable means for the head and passing through the cover plate,

an adjustable drive shaft for operating the drills; means for rotating the drive. shaft, means for feeding the drills into the work, and four independent operating stop means carried by the drill head and engaging the work during drilling, one of said stop means positioned each side of the drill head near the edge thereof.

MILTON s. WUNDERLICH 

